Haller MJ, et al. - A three-arm, randomized, double-masked, placebo-controlled trial was performed to test the premise that low-dose anti-thymocyte globulin (ATG)/granulocyte colony-stimulating factor (GCSF) or low-dose ATG alone would slow the decline of β-cell function in patients with new-onset type 1 diabetes (T1D) (duration <100 days). Findings revealed that low-dose ATG slowed the decline of C-peptide and lowered HbA_1c in new-onset T1D. Researchers found that the addition of GCSF did not enhance C-peptide preservation afforded by low-dose ATG.

Methods

• This trial was performed by the Type 1 Diabetes TrialNet Study Group in 89 subjects: 29 subjects randomized to ATG (2.5 mg/kg intravenously) followed by pegylated GCSF (6 mg subcutaneously every 2 weeks for 6 doses), 29 to ATG alone (2.5 mg/kg), and 31 to placebo.
• Mean area under the curve (AUC) C-peptide during a 2-h mixed-meal tolerance test 1 year after initiation of therapy was the primary end point.
• Researchers defined significance as one-sided P value < 0.025.

Results

• The study results showed that the 1-year mean AUC C-peptide was significantly higher in subjects treated with ATG (0.646 nmol/L) vs placebo (0.406 nmol/L) (P= 0.0003) but not in those treated with ATG/GCSF (0.528 nmol/L) vs placebo (P=0.031).
• Findings revealed that HbA_1c was significantly reduced at 1 year in subjects treated with ATG and ATG/GCSF, P=0.002 and 0.011, respectively.